The present invention relates to a system for preventing the percolation of fuel in an intake passage of a carburetor.
Conventionally, there has been proposed various means for preventing the percolation of fuel in the carburetor, such as: insulating of the carburetor by a thermal insulator; ventilation of an engine space of a vehicle for radiating the heat in order to suppress an increase in the temperature of the carburetor; cooling of the carburetor by a fan; and circulation of gasoline from the float chamber of the carburetor to the fuel tank in order to cool the gasoline stored in the float chamber.
However, in recent years, in view of the stylish design of the car, the engine space is designed to have a small capacity. Accordingly, it is difficult to occupy a large space in the engine space for providing ventilating means or a fan, and insulating the carburetor is not sufficient to prevent the percolation of fuel since the heat capacity of the carburetor is large. Further, the circulation system of gasoline between the float chamber and the fuel tank appears to be unreliable in effect.